package com.ciaojian.core.util;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class Base64 {
	
	private static final Logger logger = LoggerFactory.getLogger(Base64.class);

	/**
	 * The equals sign (=) as a byte.
	 */
	private final static byte EQUALS_SIGN = (byte) '=';
	/**
	 * The 64 valid Base64 values.
	 */
	private final static byte[] ALPHABET;
	/**
	 * Maximum line length (76) of Base64 output.
	 */
	private final static int MAX_LINE_LENGTH = 76;
	/**
	 * The new line character (\n) as a byte.
	 */
	private final static byte NEW_LINE = (byte) '\n';
	/**
	 * Specify encoding.
	 */
	public final static int ENCODE = 1;
	/**
	 * Translates a Base64 value to either its 6-bit reconstruction value or a
	 * negative number indicating some other meaning.
	 */
	private final static byte[] DECODABET = { -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal
																					// 0
																					// -
																					// 8
			-5, -5, // Whitespace: Tab and Linefeed
			-9, -9, // Decimal 11 - 12
			-5, // Whitespace: Carriage Return
			-9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 -
																// 26
			-9, -9, -9, -9, -9, // Decimal 27 - 31
			-5, // Whitespace: Space
			-9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 42
			62, // Plus sign at decimal 43
			-9, -9, -9, // Decimal 44 - 46
			63, // Slash at decimal 47
			52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // Numbers zero through nine
			-9, -9, -9, // Decimal 58 - 60
			-1, // Equals sign at decimal 61
			-9, -9, -9, // Decimal 62 - 64
			0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, // Letters 'A' through
															// 'N'
			14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // Letters 'O'
															// through 'Z'
			-9, -9, -9, -9, -9, -9, // Decimal 91 - 96
			26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, // Letters 'a'
																// through 'm'
			39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // Letters 'n'
																// through 'z'
			-9, -9, -9, -9 // Decimal 123 - 126
			/*
			 * ,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 127 - 139
			 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 140 - 152
			 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 153 - 165
			 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 166 - 178
			 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 179 - 191
			 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 192 - 204
			 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 205 - 217
			 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 218 - 230
			 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 231 - 243
			 * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9 // Decimal 244 - 255
			 */
	};
	/**
	 * Don't break lines when encoding (violates strict Base64 specification)
	 */
	public final static int DONT_BREAK_LINES = 8;
	/**
	 * Specify that data should be gzip-compressed.
	 */
	public final static int GZIP = 2;
	/**
	 * No options specified. Value is zero.
	 */
	public final static int NO_OPTIONS = 0;
	private final static byte WHITE_SPACE_ENC = -5; // Indicates white space in
													// encoding
	private final static byte[] _NATIVE_ALPHABET = /*
													 * May be something funny
													 * like EBCDIC
													 */
			{ (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F', (byte) 'G', (byte) 'H',
					(byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N', (byte) 'O', (byte) 'P',
					(byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U', (byte) 'V', (byte) 'W', (byte) 'X',
					(byte) 'Y', (byte) 'Z', (byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f',
					(byte) 'g', (byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n',
					(byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't', (byte) 'u', (byte) 'v',
					(byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z', (byte) '0', (byte) '1', (byte) '2', (byte) '3',
					(byte) '4', (byte) '5', (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) '+', (byte) '/' };
	/**
	 * Preferred encoding.
	 */
	private final static String PREFERRED_ENCODING = "GBK";
	/** Determine which ALPHABET to use. */
	static {
		byte[] __bytes;
		try {
			__bytes = new String("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/")
					.getBytes(PREFERRED_ENCODING);
		} // end try
		catch (java.io.UnsupportedEncodingException use) {
			__bytes = _NATIVE_ALPHABET; // Fall back to native encoding
		} // end catch
		ALPHABET = __bytes;
	} // end static

	static String byteArrayToBase64(byte[] a) {
		return byteArrayToBase64(a, false);
	}

	/**
	 * Translates the specified byte array into an "aternate representation"
	 * Base64 string. This non-standard variant uses an alphabet that does not
	 * contain the uppercase alphabetic characters, which makes it suitable for
	 * use in situations where case-folding occurs.
	 */
	static String byteArrayToAltBase64(byte[] a) {
		return byteArrayToBase64(a, true);
	}

	private static String byteArrayToBase64(byte[] a, boolean alternate) {
		int aLen = a.length;
		int numFullGroups = aLen / 3;
		int numBytesInPartialGroup = aLen - 3 * numFullGroups;
		int resultLen = 4 * ((aLen + 2) / 3);
		StringBuffer result = new StringBuffer(resultLen);
		char[] intToAlpha = (alternate ? intToAltBase64 : intToBase64);

		// Translate all full groups from byte array elements to Base64
		int inCursor = 0;
		for (int i = 0; i < numFullGroups; i++) {
			int byte0 = a[inCursor++] & 0xff;
			int byte1 = a[inCursor++] & 0xff;
			int byte2 = a[inCursor++] & 0xff;
			result.append(intToAlpha[byte0 >> 2]);
			result.append(intToAlpha[(byte0 << 4) & 0x3f | (byte1 >> 4)]);
			result.append(intToAlpha[(byte1 << 2) & 0x3f | (byte2 >> 6)]);
			result.append(intToAlpha[byte2 & 0x3f]);
		}

		// Translate partial group if present
		if (numBytesInPartialGroup != 0) {
			int byte0 = a[inCursor++] & 0xff;
			result.append(intToAlpha[byte0 >> 2]);
			if (numBytesInPartialGroup == 1) {
				result.append(intToAlpha[(byte0 << 4) & 0x3f]);
				result.append("==");
			} else {
				// assert numBytesInPartialGroup == 2;
				int byte1 = a[inCursor++] & 0xff;
				result.append(intToAlpha[(byte0 << 4) & 0x3f | (byte1 >> 4)]);
				result.append(intToAlpha[(byte1 << 2) & 0x3f]);
				result.append('=');
			}
		}
		// assert inCursor == a.length;
		// assert result.length() == resultLen;
		return result.toString();
	}

	/**
	 * This array is a lookup table that translates 6-bit positive integer index
	 * values into their "Base64 Alphabet" equivalents as specified in Table 1
	 * of RFC 2045.
	 */
	private static final char intToBase64[] = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N',
			'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i',
			'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3',
			'4', '5', '6', '7', '8', '9', '+', '/' };

	/**
	 * This array is a lookup table that translates 6-bit positive integer index
	 * values into their "Alternate Base64 Alphabet" equivalents. This is NOT
	 * the real Base64 Alphabet as per in Table 1 of RFC 2045. This alternate
	 * alphabet does not use the capital letters. It is designed for use in
	 * environments where "case folding" occurs.
	 */
	private static final char intToAltBase64[] = { '!', '"', '#', '$', '%', '&', '\'', '(', ')', ',', '-', '.', ':',
			';', '<', '>', '@', '[', ']', '^', '`', '_', '{', '|', '}', '~', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h',
			'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2',
			'3', '4', '5', '6', '7', '8', '9', '+', '?' };

	/**
	 * Translates the specified Base64 string (as per Preferences.get(byte[]))
	 * into a byte array.
	 * 
	 * @throw IllegalArgumentException if <tt>s</tt> is not a valid Base64
	 *        string.
	 */
	public static byte[] base64ToByteArray(String s) {
		return base64ToByteArray(s, false);
	}

	/**
	 * Translates the specified "aternate representation" Base64 string into a
	 * byte array.
	 * 
	 * @throw IllegalArgumentException or ArrayOutOfBoundsException if
	 *        <tt>s</tt> is not a valid alternate representation Base64 string.
	 */
	static byte[] altBase64ToByteArray(String s) {
		return base64ToByteArray(s, true);
	}

	private static byte[] base64ToByteArray(String s, boolean alternate) {
		byte[] alphaToInt = (alternate ? altBase64ToInt : base64ToInt);
		int sLen = s.length();
		int numGroups = sLen / 4;
		if (4 * numGroups != sLen)
			throw new IllegalArgumentException("String length must be a multiple of four.");
		int missingBytesInLastGroup = 0;
		int numFullGroups = numGroups;
		if (sLen != 0) {
			if (s.charAt(sLen - 1) == '=') {
				missingBytesInLastGroup++;
				numFullGroups--;
			}
			if (s.charAt(sLen - 2) == '=')
				missingBytesInLastGroup++;
		}
		byte[] result = new byte[3 * numGroups - missingBytesInLastGroup];

		// Translate all full groups from base64 to byte array elements
		int inCursor = 0, outCursor = 0;
		for (int i = 0; i < numFullGroups; i++) {
			int ch0 = base64toInt(s.charAt(inCursor++), alphaToInt);
			int ch1 = base64toInt(s.charAt(inCursor++), alphaToInt);
			int ch2 = base64toInt(s.charAt(inCursor++), alphaToInt);
			int ch3 = base64toInt(s.charAt(inCursor++), alphaToInt);
			result[outCursor++] = (byte) ((ch0 << 2) | (ch1 >> 4));
			result[outCursor++] = (byte) ((ch1 << 4) | (ch2 >> 2));
			result[outCursor++] = (byte) ((ch2 << 6) | ch3);
		}

		// Translate partial group, if present
		if (missingBytesInLastGroup != 0) {
			int ch0 = base64toInt(s.charAt(inCursor++), alphaToInt);
			int ch1 = base64toInt(s.charAt(inCursor++), alphaToInt);
			result[outCursor++] = (byte) ((ch0 << 2) | (ch1 >> 4));

			if (missingBytesInLastGroup == 1) {
				int ch2 = base64toInt(s.charAt(inCursor++), alphaToInt);
				result[outCursor++] = (byte) ((ch1 << 4) | (ch2 >> 2));
			}
		}
		// assert inCursor == s.length()-missingBytesInLastGroup;
		// assert outCursor == result.length;
		return result;
	}

	/**
	 * Translates the specified character, which is assumed to be in the "Base
	 * 64 Alphabet" into its equivalent 6-bit positive integer.
	 * 
	 * @throw IllegalArgumentException or ArrayOutOfBoundsException if c is not
	 *        in the Base64 Alphabet.
	 */
	private static int base64toInt(char c, byte[] alphaToInt) {
		int result = alphaToInt[c];
		if (result < 0)
			throw new IllegalArgumentException("Illegal character " + c);
		return result;
	}

	/**
	 * This array is a lookup table that translates unicode characters drawn
	 * from the "Base64 Alphabet" (as specified in Table 1 of RFC 2045) into
	 * their 6-bit positive integer equivalents. Characters that are not in the
	 * Base64 alphabet but fall within the bounds of the array are translated to
	 * -1.
	 */
	private static final byte base64ToInt[] = { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
			-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1,
			-1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8,
			9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, -1, 26, 27, 28, 29,
			30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 };

	/**
	 * This array is the analogue of base64ToInt, but for the nonstandard
	 * variant that avoids the use of uppercase alphabetic characters.
	 */
	private static final byte altBase64ToInt[] = { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
			-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, -1, 62, 9, 10,
			11, -1, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 12, 13, 14, -1, 15, 63, 16, -1, -1, -1, -1, -1, -1, -1, -1,
			-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 17, -1, 18, 19, 21, 20, 26, 27, 28,
			29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 22, 23, 24,
			25 };

	public static void main(String args[]) {
		int numRuns = Integer.parseInt(args[0]);
		int numBytes = Integer.parseInt(args[1]);
		java.util.Random rnd = new java.util.Random();
		for (int i = 0; i < numRuns; i++) {
			for (int j = 0; j < numBytes; j++) {
				byte[] arr = new byte[j];
				for (int k = 0; k < j; k++)
					arr[k] = (byte) rnd.nextInt();

				String s = byteArrayToBase64(arr);
				byte[] b = base64ToByteArray(s);
				if (!java.util.Arrays.equals(arr, b))
					logger.info("Dismal failure!");

				s = byteArrayToAltBase64(arr);
				b = altBase64ToByteArray(s);
				if (!java.util.Arrays.equals(arr, b))
					logger.info("Alternate dismal failure!");
			}
		}
	}

	/**
	 * Decodes the first four bytes of array <var>fourBytes</var> and returns an
	 * array up to three bytes long with the decoded values.
	 *
	 * @param fourBytes
	 *            the array with Base64 content
	 * @return array with decoded values
	 * @since 1.3
	 */
	private static byte[] decode4to3(byte[] fourBytes) {
		byte[] outBuff1 = new byte[3];
		int count = decode4to3(fourBytes, 0, outBuff1, 0);
		byte[] outBuff2 = new byte[count];

		for (int i = 0; i < count; i++)
			outBuff2[i] = outBuff1[i];

		return outBuff2;
	}

	/**
	 * Decodes four bytes from array <var>source</var> and writes the resulting
	 * bytes (up to three of them) to <var>destination</var>. The source and
	 * destination arrays can be manipulated anywhere along their length by
	 * specifying <var>srcOffset</var> and <var>destOffset</var>. This method
	 * does not check to make sure your arrays are large enough to accomodate
	 * <var>srcOffset</var> + 4 for the <var>source</var> array or
	 * <var>destOffset</var> + 3 for the <var>destination</var> array. This
	 * method returns the actual number of bytes that were converted from the
	 * Base64 encoding.
	 *
	 * @param source
	 *            the array to convert
	 * @param srcOffset
	 *            the index where conversion begins
	 * @param destination
	 *            the array to hold the conversion
	 * @param destOffset
	 *            the index where output will be put
	 * @return the number of decoded bytes converted
	 * @since 1.3
	 */
	private static int decode4to3(byte[] source, int srcOffset, byte[] destination, int destOffset) {
		// Example: Dk==
		if (source[srcOffset + 2] == EQUALS_SIGN) {
			// Two ways to do the same thing. Don't know which way I like best.
			// int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6
			// )
			// | ( ( DECODABET[ source[ srcOffset + 1] ] << 24 ) >>> 12 );
			int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
					| ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12);

			destination[destOffset] = (byte) (outBuff >>> 16);
			return 1;
		}

		// Example: DkL=
		else if (source[srcOffset + 3] == EQUALS_SIGN) {
			// Two ways to do the same thing. Don't know which way I like best.
			// int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6
			// )
			// | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
			// | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 );
			int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
					| ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12)
					| ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6);

			destination[destOffset] = (byte) (outBuff >>> 16);
			destination[destOffset + 1] = (byte) (outBuff >>> 8);
			return 2;
		}

		// Example: DkLE
		else {
			try {
				// Two ways to do the same thing. Don't know which way I like
				// best.
				// int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 )
				// >>> 6 )
				// | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
				// | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 )
				// | ( ( DECODABET[ source[ srcOffset + 3 ] ] << 24 ) >>> 24 );
				int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
						| ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12)
						| ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6)
						| ((DECODABET[source[srcOffset + 3]] & 0xFF));

				destination[destOffset] = (byte) (outBuff >> 16);
				destination[destOffset + 1] = (byte) (outBuff >> 8);
				destination[destOffset + 2] = (byte) (outBuff);

				return 3;
			} catch (Exception e) {
				logger.info("" + source[srcOffset] + ": " + (DECODABET[source[srcOffset]]));
				logger.info("" + source[srcOffset + 1] + ": " + (DECODABET[source[srcOffset + 1]]));
				logger.info("" + source[srcOffset + 2] + ": " + (DECODABET[source[srcOffset + 2]]));
				logger.info("" + source[srcOffset + 3] + ": " + (DECODABET[source[srcOffset + 3]]));
				return -1;
			} // e nd catch
		}
	} // end decodeToBytes

	/**
	 * Encodes a byte array into Base64 notation. Does not GZip-compress data.
	 *
	 * @param source
	 *            The data to convert
	 * @since 1.4
	 */
	public static String encodeBytes(byte[] source) {
		return encodeBytes(source, 0, source.length, NO_OPTIONS);
	} // end encodeBytes

	/**
	 * Encodes a byte array into Base64 notation.
	 * <p/>
	 * Valid options:
	 * 
	 * <pre>
	 *   GZIP: gzip-compresses object before encoding it.
	 *   DONT_BREAK_LINES: don't break lines at 76 characters
	 *     <i>Note: Technically, this makes your encoding non-compliant.</i>
	 * </pre>
	 * <p/>
	 * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or
	 * <p/>
	 * Example:
	 * <code>encodeBytes( myData, Base64.GZIP | Base64.DONT_BREAK_LINES )</code>
	 *
	 * @param source
	 *            The data to convert
	 * @param options
	 *            Specified options
	 * @see Base64#GZIP
	 * @see Base64#DONT_BREAK_LINES
	 * @since 2.0
	 */
	public static String encodeBytes(byte[] source, int options) {
		return encodeBytes(source, 0, source.length, options);
	} // end encodeBytes

	/**
	 * Encodes a byte array into Base64 notation. Does not GZip-compress data.
	 *
	 * @param source
	 *            The data to convert
	 * @param off
	 *            Offset in array where conversion should begin
	 * @param len
	 *            Length of data to convert
	 * @since 1.4
	 */
	public static String encodeBytes(byte[] source, int off, int len) {
		return encodeBytes(source, off, len, NO_OPTIONS);
	} // end encodeBytes

	/**
	 * Encodes a byte array into Base64 notation.
	 * <p/>
	 * Valid options:
	 * 
	 * <pre>
	 *   GZIP: gzip-compresses object before encoding it.
	 *   DONT_BREAK_LINES: don't break lines at 76 characters
	 *     <i>Note: Technically, this makes your encoding non-compliant.</i>
	 * </pre>
	 * <p/>
	 * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or
	 * <p/>
	 * Example:
	 * <code>encodeBytes( myData, Base64.GZIP | Base64.DONT_BREAK_LINES )</code>
	 *
	 * @param source
	 *            The data to convert
	 * @param off
	 *            Offset in array where conversion should begin
	 * @param len
	 *            Length of data to convert
	 * @param options
	 *            Specified options
	 * @see Base64#GZIP
	 * @see Base64#DONT_BREAK_LINES
	 * @since 2.0
	 */
	public static String encodeBytes(byte[] source, int off, int len, int options) {
		// Isolate options
		int dontBreakLines = (options & DONT_BREAK_LINES);
		int gzip = (options & GZIP);

		// Compress?
		if (gzip == GZIP) {
			java.io.ByteArrayOutputStream baos = null;
			java.util.zip.GZIPOutputStream gzos = null;
			OutputStream b64os = null;

			try {
				// GZip -> Base64 -> ByteArray
				baos = new java.io.ByteArrayOutputStream();
				b64os = new OutputStream(baos, ENCODE | dontBreakLines);
				gzos = new java.util.zip.GZIPOutputStream(b64os);

				gzos.write(source, off, len);
				gzos.close();
			} // end try
			catch (java.io.IOException e) {
				return null;
			} // end catch
			finally {
				try {
					gzos.close();
				} catch (Exception e) {
				}
				try {
					b64os.close();
				} catch (Exception e) {
				}
				try {
					baos.close();
				} catch (Exception e) {
				}
			} // end finally

			// Return value according to relevant encoding.
			try {
				return new String(baos.toByteArray(), PREFERRED_ENCODING);
			} // end try
			catch (java.io.UnsupportedEncodingException uue) {
				return new String(baos.toByteArray());
			} // end catch
		} // end if: compress

		// Else, don't compress. Better not to use streams at all then.
		else {
			// Convert option to boolean in way that code likes it.
			boolean breakLines = dontBreakLines == 0;

			int len43 = len * 4 / 3;
			byte[] outBuff = new byte[(len43) // Main 4:3
					+ ((len % 3) > 0 ? 4 : 0) // Account for padding
					+ (breakLines ? (len43 / MAX_LINE_LENGTH) : 0)]; // New
																		// lines
			int d = 0;
			int e = 0;
			int len2 = len - 2;
			int lineLength = 0;
			for (; d < len2; d += 3, e += 4) {
				encode3to4(source, d + off, 3, outBuff, e);

				lineLength += 4;
				if (breakLines && lineLength == MAX_LINE_LENGTH) {
					outBuff[e + 4] = NEW_LINE;
					e++;
					lineLength = 0;
				} // end if: end of line
			} // en dfor: each piece of array

			if (d < len) {
				encode3to4(source, d + off, len - d, outBuff, e);
				e += 4;
			} // end if: some padding needed

			// Return value according to relevant encoding.
			try {
				return new String(outBuff, 0, e, PREFERRED_ENCODING);
			} // end try
			catch (java.io.UnsupportedEncodingException uue) {
				return new String(outBuff, 0, e);
			} // end catch

		} // end else: don't compress

	} // end encodeBytes

	/**
	 * Encodes the first three bytes of array <var>threeBytes</var> and returns
	 * a four-byte array in Base64 notation.
	 *
	 * @param threeBytes
	 *            the array to convert
	 * @return four byte array in Base64 notation.
	 * @since 1.3
	 */
	private static byte[] encode3to4(byte[] threeBytes) {
		return encode3to4(threeBytes, 3);
	} // end encodeToBytes

	/**
	 * Encodes up to the first three bytes of array <var>threeBytes</var> and
	 * returns a four-byte array in Base64 notation. The actual number of
	 * significant bytes in your array is given by <var>numSigBytes</var>. The
	 * array <var>threeBytes</var> needs only be as big as
	 * <var>numSigBytes</var>.
	 *
	 * @param threeBytes
	 *            the array to convert
	 * @param numSigBytes
	 *            the number of significant bytes in your array
	 * @return four byte array in Base64 notation.
	 * @since 1.3
	 */
	private static byte[] encode3to4(byte[] threeBytes, int numSigBytes) {
		byte[] dest = new byte[4];
		encode3to4(threeBytes, 0, numSigBytes, dest, 0);
		return dest;
	}

	/**
	 * Encodes up to the first three bytes of array <var>threeBytes</var> and
	 * returns a four-byte array in Base64 notation. The actual number of
	 * significant bytes in your array is given by <var>numSigBytes</var>. The
	 * array <var>threeBytes</var> needs only be as big as
	 * <var>numSigBytes</var>. Code can reuse a byte array by passing a
	 * four-byte array as <var>b4</var>.
	 *
	 * @param b4
	 *            A reusable byte array to reduce array instantiation
	 * @param threeBytes
	 *            the array to convert
	 * @param numSigBytes
	 *            the number of significant bytes in your array
	 * @return four byte array in Base64 notation.
	 * @since 1.5.1
	 */
	private static byte[] encode3to4(byte[] b4, byte[] threeBytes, int numSigBytes) {
		encode3to4(threeBytes, 0, numSigBytes, b4, 0);
		return b4;
	} // end encode3to4

	/**
	 * Encodes up to three bytes of the array <var>source</var> and writes the
	 * resulting four Base64 bytes to <var>destination</var>. The source and
	 * destination arrays can be manipulated anywhere along their length by
	 * specifying <var>srcOffset</var> and <var>destOffset</var>. This method
	 * does not check to make sure your arrays are large enough to accomodate
	 * <var>srcOffset</var> + 3 for the <var>source</var> array or
	 * <var>destOffset</var> + 4 for the <var>destination</var> array. The
	 * actual number of significant bytes in your array is given by
	 * <var>numSigBytes</var>.
	 *
	 * @param source
	 *            the array to convert
	 * @param srcOffset
	 *            the index where conversion begins
	 * @param numSigBytes
	 *            the number of significant bytes in your array
	 * @param destination
	 *            the array to hold the conversion
	 * @param destOffset
	 *            the index where output will be put
	 * @return the <var>destination</var> array
	 * @since 1.3
	 */
	private static byte[] encode3to4(byte[] source, int srcOffset, int numSigBytes, byte[] destination,
			int destOffset) {
		// 1 2 3
		// 01234567890123456789012345678901 Bit position
		// --------000000001111111122222222 Array position from threeBytes
		// --------| || || || | Six bit groups to index ALPHABET
		// >>18 >>12 >> 6 >> 0 Right shift necessary
		// 0x3f 0x3f 0x3f Additional AND

		// Create buffer with zero-padding if there are only one or two
		// significant bytes passed in the array.
		// We have to shift left 24 in order to flush out the 1's that appear
		// when Java treats a value as negative that is cast from a byte to an
		// int.
		int inBuff = (numSigBytes > 0 ? ((source[srcOffset] << 24) >>> 8) : 0)
				| (numSigBytes > 1 ? ((source[srcOffset + 1] << 24) >>> 16) : 0)
				| (numSigBytes > 2 ? ((source[srcOffset + 2] << 24) >>> 24) : 0);

		switch (numSigBytes) {
		case 3:
			destination[destOffset] = ALPHABET[(inBuff >>> 18)];
			destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
			destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f];
			destination[destOffset + 3] = ALPHABET[(inBuff) & 0x3f];
			return destination;

		case 2:
			destination[destOffset] = ALPHABET[(inBuff >>> 18)];
			destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
			destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f];
			destination[destOffset + 3] = EQUALS_SIGN;
			return destination;

		case 1:
			destination[destOffset] = ALPHABET[(inBuff >>> 18)];
			destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
			destination[destOffset + 2] = EQUALS_SIGN;
			destination[destOffset + 3] = EQUALS_SIGN;
			return destination;

		default:
			return destination;
		} // end switch
	} // end encode3to4

	/**
	 * A outputStream will write data to another {@link java.io.OutputStream},
	 * given in the constructor, and encode/decode to/from Base64 notation on
	 * the fly.
	 *
	 * @see Base64
	 * @see java.io.FilterOutputStream
	 * @since 1.3
	 */
	public static class OutputStream extends java.io.FilterOutputStream {
		private int options;
		private boolean encode;
		private int position;
		private byte[] buffer;
		private int bufferLength;
		private int lineLength;
		private boolean breakLines;
		private byte[] b4; // Scratch used in a few places
		private boolean suspendEncoding;

		/**
		 * Constructs a OutputStream in ENCODE mode.
		 *
		 * @param out
		 *            the {@link java.io.OutputStream} to which data will be
		 *            written.
		 * @since 1.3
		 */
		public OutputStream(java.io.OutputStream out) {
			this(out, ENCODE);
		} // end constructor

		/**
		 * Constructs a OutputStream in either ENCODE or DECODE mode.
		 * <p/>
		 * Valid options:
		 * 
		 * <pre>
		 *   ENCODE or DECODE: Encode or Decode as data is read.
		 *   DONT_BREAK_LINES: don't break lines at 76 characters
		 *     (only meaningful when encoding)
		 *     <i>Note: Technically, this makes your encoding non-compliant.</i>
		 * </pre>
		 * <p/>
		 * Example: <code>new Base64.OutputStream( out, Base64.ENCODE )</code>
		 *
		 * @param out
		 *            the {@link java.io.OutputStream} to which data will be
		 *            written.
		 * @param options
		 *            Specified options.
		 * @see Base64#ENCODE
		 * @see Base64#DECODE
		 * @see Base64#DONT_BREAK_LINES
		 * @since 1.3
		 */
		public OutputStream(java.io.OutputStream out, int options) {
			super(out);
			this.options = options;
			this.breakLines = (options & DONT_BREAK_LINES) != DONT_BREAK_LINES;
			this.encode = (options & ENCODE) == ENCODE;
			this.bufferLength = encode ? 3 : 4;
			this.buffer = new byte[bufferLength];
			this.position = 0;
			this.lineLength = 0;
			this.suspendEncoding = false;
			this.b4 = new byte[4];
		} // end constructor

		/**
		 * Writes the byte to the output stream after converting to/from Base64
		 * notation. When encoding, bytes are buffered three at a time before
		 * the output stream actually gets a write() call. When decoding, bytes
		 * are buffered four at a time.
		 *
		 * @param theByte
		 *            the byte to write
		 * @since 1.3
		 */
		public void write(int theByte) throws java.io.IOException {
			// Encoding suspended?
			if (suspendEncoding) {
				super.out.write(theByte);
				return;
			} // end if: supsended

			// Encode?
			if (encode) {
				buffer[position++] = (byte) theByte;
				if (position >= bufferLength) // Enough to encode.
				{
					out.write(encode3to4(b4, buffer, bufferLength));

					lineLength += 4;
					if (breakLines && lineLength >= MAX_LINE_LENGTH) {
						out.write(NEW_LINE);
						lineLength = 0;
					} // end if: end of line

					position = 0;
				} // end if: enough to output
			} // end if: encoding

			// Else, Decoding
			else {
				// Meaningful Base64 character?
				if (DECODABET[theByte & 0x7f] > WHITE_SPACE_ENC) {
					buffer[position++] = (byte) theByte;
					if (position >= bufferLength) // Enough to output.
					{
						int len = Base64.decode4to3(buffer, 0, b4, 0);
						out.write(b4, 0, len);
						// out.write( Base64.decode4to3( buffer ) );
						position = 0;
					} // end if: enough to output
				} // end if: meaningful base64 character
				else if (DECODABET[theByte & 0x7f] != WHITE_SPACE_ENC) {
					throw new java.io.IOException("Invalid character in Base64 data.");
				} // end else: not white space either
			} // end else: decoding
		} // end write

		/**
		 * Decodes the first four bytes of array <var>fourBytes</var> and
		 * returns an array up to three bytes long with the decoded values.
		 *
		 * @param fourBytes
		 *            the array with Base64 content
		 * @return array with decoded values
		 * @since 1.3
		 */
		private static byte[] decode4to3(byte[] fourBytes) {
			byte[] outBuff1 = new byte[3];
			int count = decode4to3(fourBytes, 0, outBuff1, 0);
			byte[] outBuff2 = new byte[count];

			for (int i = 0; i < count; i++)
				outBuff2[i] = outBuff1[i];

			return outBuff2;
		}

		/**
		 * Decodes four bytes from array <var>source</var> and writes the
		 * resulting bytes (up to three of them) to <var>destination</var>. The
		 * source and destination arrays can be manipulated anywhere along their
		 * length by specifying <var>srcOffset</var> and <var>destOffset</var>.
		 * This method does not check to make sure your arrays are large enough
		 * to accomodate <var>srcOffset</var> + 4 for the <var>source</var>
		 * array or <var>destOffset</var> + 3 for the <var>destination</var>
		 * array. This method returns the actual number of bytes that were
		 * converted from the Base64 encoding.
		 *
		 * @param source
		 *            the array to convert
		 * @param srcOffset
		 *            the index where conversion begins
		 * @param destination
		 *            the array to hold the conversion
		 * @param destOffset
		 *            the index where output will be put
		 * @return the number of decoded bytes converted
		 * @since 1.3
		 */
		private static int decode4to3(byte[] source, int srcOffset, byte[] destination, int destOffset) {
			// Example: Dk==
			if (source[srcOffset + 2] == EQUALS_SIGN) {
				// Two ways to do the same thing. Don't know which way I like
				// best.
				// int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 )
				// >>> 6 )
				// | ( ( DECODABET[ source[ srcOffset + 1] ] << 24 ) >>> 12 );
				int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
						| ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12);

				destination[destOffset] = (byte) (outBuff >>> 16);
				return 1;
			}

			// Example: DkL=
			else if (source[srcOffset + 3] == EQUALS_SIGN) {
				// Two ways to do the same thing. Don't know which way I like
				// best.
				// int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 )
				// >>> 6 )
				// | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
				// | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 );
				int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
						| ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12)
						| ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6);

				destination[destOffset] = (byte) (outBuff >>> 16);
				destination[destOffset + 1] = (byte) (outBuff >>> 8);
				return 2;
			}

			// Example: DkLE
			else {
				try {
					// Two ways to do the same thing. Don't know which way I
					// like best.
					// int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24
					// ) >>> 6 )
					// | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12
					// )
					// | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18
					// )
					// | ( ( DECODABET[ source[ srcOffset + 3 ] ] << 24 ) >>> 24
					// );
					int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
							| ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12)
							| ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6)
							| ((DECODABET[source[srcOffset + 3]] & 0xFF));

					destination[destOffset] = (byte) (outBuff >> 16);
					destination[destOffset + 1] = (byte) (outBuff >> 8);
					destination[destOffset + 2] = (byte) (outBuff);

					return 3;
				} catch (Exception e) {
					logger.info("" + source[srcOffset] + ": " + (DECODABET[source[srcOffset]]));
					logger.info("" + source[srcOffset + 1] + ": " + (DECODABET[source[srcOffset + 1]]));
					logger.info("" + source[srcOffset + 2] + ": " + (DECODABET[source[srcOffset + 2]]));
					logger.info("" + source[srcOffset + 3] + ": " + (DECODABET[source[srcOffset + 3]]));
					return -1;
				} // e nd catch
			}
		} // end decodeToBytes

		/**
		 * Calls {@link #write} repeatedly until <var>len</var> bytes are
		 * written.
		 *
		 * @param theBytes
		 *            array from which to read bytes
		 * @param off
		 *            offset for array
		 * @param len
		 *            max number of bytes to read into array
		 * @since 1.3
		 */
		public void write(byte[] theBytes, int off, int len) throws java.io.IOException {
			// Encoding suspended?
			if (suspendEncoding) {
				super.out.write(theBytes, off, len);
				return;
			} // end if: supsended

			for (int i = 0; i < len; i++) {
				write(theBytes[off + i]);
			} // end for: each byte written

		} // end write

		/**
		 * Method added by PHIL. [Thanks, PHIL. -Rob] This pads the buffer
		 * without closing the stream.
		 */
		public void flushBase64() throws java.io.IOException {
			if (position > 0) {
				if (encode) {
					out.write(encode3to4(b4, buffer, position));
					position = 0;
				} // end if: encoding
				else {
					throw new java.io.IOException("Base64 input not properly padded.");
				} // end else: decoding
			} // end if: buffer partially full

		} // end flush

		/**
		 * Flushes and closes (I think, in the superclass) the stream.
		 *
		 * @since 1.3
		 */
		public void close() throws java.io.IOException {
			// 1. Ensure that pending characters are written
			flushBase64();

			// 2. Actually close the stream
			// Base class both flushes and closes.
			super.close();

			buffer = null;
			out = null;
		} // end close

		/**
		 * Suspends encoding of the stream. May be helpful if you need to embed
		 * a piece of base640-encoded data in a stream.
		 *
		 * @since 1.5.1
		 */
		public void suspendEncoding() throws java.io.IOException {
			flushBase64();
			this.suspendEncoding = true;
		} // end suspendEncoding

		/**
		 * Resumes encoding of the stream. May be helpful if you need to embed a
		 * piece of base640-encoded data in a stream.
		 *
		 * @since 1.5.1
		 */
		public void resumeEncoding() {
			this.suspendEncoding = false;
		} // end resumeEncoding

	} // end inner class OutputStream
}
